SAN DIEGO -- Even as mediation continued over a sexual-harassment lawsuit that could lead to Mayor Bob Filner's resignation, another woman alleged Wednesday that he made unwanted sexual advances.

Dianne York, president and chief executive of the Spa of La Jolla, told CNN the incident occurred after a meeting three months ago in his office at City Hall. She had met with Filner about a foreclosure.

While pictures were being taken, York said, Filner placed his hand on her buttocks.

"I felt extremely violated," she told CNN on Wednesday.

Meanwhile, mediation over a lawsuit filed by a former Filner staff member is said to be continuing after all-day sessions Monday and Tuesday.

Present at the Tuesday session, overseen by a retired federal judge, were Filner; his attorney from the Irvine firm Payne & Fears; City Atty. Jan Goldsmith and City Council members Kevin Faulconer and Todd Gloria.

At the end of Tuesday's mediation, Goldsmith would say only that mediation can be a lengthy process. Retired jurist J. Lawrence Irving has told all participants not to talk specifics.

Filner, 70, a Democrat, had promised to return to City Hall on Monday after his two weeks of what was described as intensive behavioral therapy. But he has not been seen at City Hall.

At issue in the mediation could be an offer by the city to trade Filner's resignation for financial assistance in paying his legal bills and any judgment from the Jackson lawsuit.

The City Council has refused to pay Filner's legal bills and also threatened to sue him to recover any damages assessed against the city in the lawsuit.

All nine members of the council have called for his resignation, along with the local Democratic party and numerous state officeholders. On Friday, the Democratic National Committee, meeting in Arizona, is expected to endorse a resolution calling for his resignation.

A recall movement against Filner began gathering signatures this week. Recall activists must collect more than 101,000 signatures of registered voters to qualify a recall for the ballot.

More than a dozen women have accused Filner of making sexual advances and inappropriate comments.